Abstract

OBJECTIVE:

The efficacy and safety of abatacept in patients with juvenile idiopathic arthritis (JIA) who experienced an inadequate response to disease-modifying antirheumatic drugs were previously established in a phase III study that included a 4-month open-label lead-in period, a 6-month double-blind withdrawal period, and a long-term extension (LTE) phase. The aim of this study was to present the safety, efficacy, and patient-reported outcomes of abatacept treatment (10 mg/kg every 4 weeks) during the LTE phase, for up to 7 years of followup.

METHODS:

Patients enrolled in the phase III trial could enter the open-label LTE phase if they had not achieved a response to treatment at month 4 or if they had received abatacept or placebo during the double-blind period.

Disposition of the patients with juvenile idiopathic arthritis during the long‐term extension (LTE) phase. ∗ = One patient withdrew consent and left the study during the double‐blind (DB) treatment period. † = The reasons for discontinuation were not reported.

Proportions of juvenile idiopathic arthritis patients meeting the American College of Rheumatology (ACR) Pediatric 30 (Pedi 30), Pedi 50, Pedi 70, and Pedi 90 criteria for improvement and the proportions achieving an inactive disease status over time. A, Combined group of patients who received abatacept during the 6‐month double‐blind withdrawal period and those who received placebo during the 6‐month double‐blind withdrawal period. B, Patients who did not achieve an ACR Pedi 30 response during the initial 4‐month open‐label lead‐in period and who entered the long‐term extension (LTE) phase directly. In A and B, data were derived from as‐observed analyses based on all patients who entered the open‐label LTE. Bars show the 95% confidence intervals. n = number of patients with available data on each visit day. C, Intent‐to‐treat population. ACR Pedi responses throughout the LTE phase were also evaluated in a post hoc intent‐to‐treat analysis based on all 190 patients who had entered the lead‐in phase of the trial, with any patient who discontinued at any point considered a nonresponder. A total of 76 patients remained in the study and had efficacy data available on day 1,765.